A method for the manufacturing of metallic matrix composites

ABSTRACT

A method for the manufacturing of metallic matrix composites through plastic working is disclosed. In the method, the plastic working charge is in the form of wires, tape or tapes or foil, which is the first component being covered with the second component or components with granulation less than 100 μm, after which they are connected by reciprocal surface contact, forming weaved bundles, and then the connected elements which form the charge material advantageously undergo initial rolling or drawing and in all cases the principal process, which is extrusion performed on a rolling mill with circumferential grooves, where between rollers a closing matrix is placed, rotating in reverse to its axis by an angle of ±20° advantageously ±12°, with a frequency up to 50 Hz, advantageously 15 Hz.

CROSS-REFERENCE TO RELATED U.S. APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT

Not applicable.

REFERENCE TO AN APPENDIX SUBMITTED ON COMPACT DISC

Not applicable.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The subject of the invention is a method for the manufacturing ofmetallic matrix composites through plastic working

2. Description of Related Art Including Information Disclosed Under 37CFR 1.97 and 37 CFR 1.98.

Metallurgical methods of manufacturing of metallic matrix compositesconsisting of adding to a liquid metal or alloy of small metallicelements with a higher melting temperature or of ceramic powder, mixingthe bath and cooling it in order to obtain full crystallisation.

A method is also known where liquid metal or alloy is poured over one ofthe components in the form of a set of thin wires. After setting, acompact composite is obtained.

The aforementioned methods may be used both for individual manufacturingand in continuous processes.

Another method of composite manufacture is based on powder metallurgyand consists of mixing powdered components with specific chemicalcomposition, size and shapes, mechanically compacting and then sinteringthem.

There is a need for the manufacturing of composites from componentswhich do not mix to the required degree in known processes, inparticular metallurgic processes.

BRIEF SUMMARY OF THE INVENTION

The essence of the invention, which is a method for the manufacturing ofmetallic matrix composites through plastic working, advantageously in acontinuous pressing extrusion process with oscillatory twisting,consists of the plastic working charge in the form of wires, tape ortapes or foil, which is the first component being covered with thesecond component or components with granulation less than 100 μm, afterwhich they are connected by reciprocal surface contact, forming weavedbundles, and then the connected elements which form the charge materialundergo initial rolling or drawing and the principal process, which ispressing performed on a rolling mill with circumferential grooves, wherebetween rollers a closing matrix is placed, rotating in reverse to itsaxis by an angle of ±20° advantageously ±12°, with a frequency up to 50Hz, advantageously 15 Hz.

It is advantageous when the wires covered by the second component areplaced in a bundle and twisted together with a twist of (0.8-0.2),advantageously 0.5 rotation per 100 mm of length.

It is also advantageous when the metal tape or foil covered by thesecond component is twisted in spiral coils, and multiple coils areplaced in a bundle and twisted together.

Moreover it is advantageous when the charge undergoing the main processof pressing is introduced into the grooves between the rolling mill'srolls with the shorter axis of its perpendicular cross-section parallelto the roll axis.

It is also advantageous when the first component is a metal tape ortapes.

It is moreover advantageous when the first component is a metal foil orfoils.

Moreover it is advantageous when the first component is connected wiresand foil, connected wires and metal tape, connected foil and metaltapes, and the second component is ground aluminium, advantageously inthe form of dust.

It is additionally advantageous when the metal foil covered by thesecond component is twisted in spiral coils, and multiple coils areplaced in a bundle and twisted together.

The use of the solution presented in the invention enables the followingtechnical and utility effects:

-   -   avoiding the metallurgical stage for the manufacturing of        composites,    -   the possibility of manufacturing composites from components        which do not join together in a metallurgical process,    -   the possibility of manufacturing composites using commonly        available components, regardless of their chemical composition        and form,    -   obtaining composites by mechanical mixing and merging,    -   a power saving process with no negative environmental impact.

DETAILED DESCRIPTION OF THE INVENTION

The method according to the invention requires the use of chargecomposed of one component in the form of wire, tape or foil, whereas thesecond or subsequent components may have the same form, or alternativelyany ground form, whereas it is advantageous when at least one of thedimensions of one of the components does not exceed 100 μm. Chargepreparation includes the placement of wire, tape or foil, andalternatively placing on their surface at least one component in groundform, or placing it in spaces between these elements, which then shouldbe twisted or braided together.

Method according to the invention consists of plastic working of acharge prepared in such a manner, advantageously in the process ofcontinuous pressing with oscillatory twisting, whereas the deformedcharge may be additionally covered, advantageously with a tape or foil.

The composite is obtained during the deformation of the charge, leadingto its mechanical mixing and merging.

The advantage of the method presented in the invention is bypassing themetallurgical stage and the use of commonly available components in asolid state, both concerning their chemical composition and their form.

Example

Copper wires with a diameter of 1.0 mm were covered on the surface withaluminium powder with a grain size of 100 μm through gas injection. Theywere placed in a bundle, which was twisted together by 0.5 of rotationfor each 100 mm of their length. A line with a diameter of 12 mm wasobtained, which underwent initial rolling on flat rolls, down to athickness of 9.5 mm. The material thus prepared formed the charge forcontinuous pressing with twisting. The process was conducted using a duorolling mill with a roll diameter of 260 mm rotating with a speed of 0.2s⁻¹ with circumferentially cut groove on each of them, which provide theclosed rollers with a circular clearance with a diameter of 10 mm. Inthis location a die was placed with a 4 mm diameter opening, filling theopening between the rollers, and was subjected to reversible rotationsalong its axis at an angle of ±12° with a frequency of 15 Hz. The finalstage of the composite manufacturing process on a copper matrixconsisted of entering the charge into the rolling mill in a manner thatthe shorter axis of its cross-section was placed in parallel to the axisof the rollers. The friction between the charge and the rotating rollersdirected it towards a reversibly rotating die, which by transferring itsmovement inside the charge located in its vicinity has caused theoccurrence of a cyclic deformation path effect, and as a consequence thepermanent connection of charge elements and reducing its flow stress,resulting in extruding the charge through the die opening. Thus acompact composite was manufactured in the shape of a 4 mm diameter wire.

1. A method for the manufacturing of metallic matrix composites throughplastic working, advantageously in a continuous extrusion process withoscillatory twisting, characterized in that the plastic working chargein the form of wires, tape or tapes or foil, which is the firstcomponent being covered with the second component or components withgranulation less than 100 μm, after which they are connected byreciprocal surface contact, forming weaved bundles, and then theconnected elements which form the charge material advantageously undergoinitial rolling or drawing and in all cases the principal process, whichis pressing performed on a rolling mill with circumferential grooves,where between rollers a closing matrix is placed, rotating in reverse toits axis by an angle of ±20° advantageously ±12°, with a frequency up to50 Hz, advantageously 15 Hz.
 2. A method in accordance with claim 1characterized in that the wires covered by the second component areplaced in a bundle and twisted together with a twist of (0.8-0.2),advantageously 0.5 rotation per 100 mm of length.
 3. A method inaccordance with claim 1, characterized in that the metal tape or foilcovered by the second component is twisted in spiral coils, and multiplecoils are placed in a bundle and twisted together.
 4. A method inaccordance with claim 1, characterized in that the charge undergoing themain process of pressing is introduced into the grooves between therolling mill's rolls with the shorter axis of its perpendicularcross-section parallel to the roll axis.
 5. A method in accordance withclaim 1, characterized in that the first component is a metal tape ortapes.
 6. A method in accordance with claim 1, characterized in that thefirst component is a metal foil or foils.
 7. A method in accordance withclaim 1, characterized in that the first component is joined wires andfoil.
 8. A method in accordance with claim 1, characterized in that thefirst component is joined wires and metal tapes.
 9. A method inaccordance with claim 1, characterized in that the first component isjoined foil and metal tapes.
 10. A method in accordance with claim 1,characterized in that the metal foil covered by the second component istwisted in spiral coils, and multiple coils are placed in a bundle andtwisted together.